Аннотация:Introduction. Long term changes in the body height and female pelvic width of North-Western Siberiaindigenous people - the Nothern Khanty and Sosva Mansi, were the subject matter of the study.Materials and discussion. The indices under examination were averaged by decade to trace the changesfrom the 1860s to 1990s. Through the birth cohorts (BiCo) from the 1860s to 1930s, the stature of ObUgrians did not alter significantly. In successive generations, up to the 1990s BiCo, there was an increase inbody height. Males have became taller by 11.3 cm, females - by 10.4 cm (p<0.0001 for both sexes). Relative(to the height of the 1930s BiCo) growth amounted to +7.18% and +7.06% for males and females respectively.In females, body proportions have changed substantially. Alongside the increase in stature, pelvic width(d. cristarum) decreased from 28.9 cm in the 1930s BiCo to 26.8 cm in the 1970s BiCo. Hence, relative pelvicwidth narrowed by 2.1% (the factor of belonging to cohort is significant, p<0.0001).Conclusion. The body height of Ob Ugrians changed unevenly. Shifts in somatic features followed aftersocial transformations. Better quality of life over the period of individual growth and development affected thedefinitive body height. Thus, the long-term changes in somatic traits of the indigenous Khanty and Mansipeople agree with the “quality of the environment” hypothesis of secular trends.